/Engine/Source/Runtime/Landscape/Classes/LandscapeProxy.h
Describes what information the export will write in a given UV channel
enum EUVMappingType { None, RelativeToComponentsBoundsUV, RelativeToProxyBoundsUV, HeightmapUV, WeightmapUV, TerrainCoordMapping_XY, TerrainCoordMapping_XZ, TerrainCoordMapping_YZ, Num, }